Steve, I heard that was a less-than-professional demonstration, also the Bigfoot people have been doing hydraulics exclusively for many years, I like their business experience. As I said, I am looking foreword at my desire to camp off the grid, and also I ain't getting any younger.
To answer my question, you do NOT need to weld the levelers on, bolting is fine.
Here are two great links:
http://tinyurl.com/29s75xk
http://www.dmbruss.com/zTige/Tige_BigFootSystem.htm